1. Field of the Invention
The present invention relates to electronic cards and more particularly to exterior shells for such cards.
2. Brief Description of Prior Developments
Electronic cards are widely used, especially for adding capacity and/or functionality to personal computers. The Personal Computer Memory Card International Association (PCMCIA) has established standards for such cards, and has categorized them as type I, type II and type III cards.
Previously cards have employed cover shields latched and/or adhesively fixed to an intermediate frame and covers laser welded or ultrasonically welded together. More recent cards employ metal shields that are directly fixed together, without a frame. However, there are difficulties experienced in having such structures maintain sufficient rigidity to withstand flexing, bending and tension forces which would be expected to be placed on it in the course of ordinary use. There is, therefore, a need for an electronic card which avoids the above mentioned difficulties.
Inherent to usage of thin sheet metal to form the outer packages of relatively large size products such as the PCMCIA Memory Card assemblies is the "Oil-Canning" noise emission, often referred to as "Click-Clack". There is a continued need to retain thin material thickness combined with a deep-draw of the two card shields half's while still eliminating such noise.